Mythbusting the metas of KanColle

Countless times, I've seen people use setups which makes me raise my eyebrows. When I questioned them as to why they chose such setups, they replied to me with either that they thought this was the meta, it looks cool, or they simply felt that it performed better.
The people who knows me will obviously predict my endless flaming and lecturing to what they're doing wrong.

This blog is a collection of my encounters with such occurrences, and it serves as a reminder to people that they should not be fooled by false meta or meme setups that have no scientific explanation backing them up as to why they are good. The subject will be listed here and I will offer you my insight on why it's either good or bad and what you could have done better instead.

Keep in mind that this blog serves to help you further optimize your fleet. If your plan was to create a meme fleet all along, then the majority of the comments here obviously don't apply to you.

Contents

Format

Investigation: An investigation will be carried out by me with the help of other people to find more information surrounding this, which in turn helps to provide us a conclusion and a verdict.

Verdict: Based on the investigations, a certain score will be given depending on what I discovered during my investigation:

FALSE: Completely false or outdated/deprecated meta.

QUESTIONABLE: There's a merit of truth, but there's usually better alternatives or the cost is too high for what you get in return.

OK: Might actually be useful in some scenarios, it got a bad reputation because it was applied in a bad way or the original meta changed somehow to what it is now.

If the samples and evidence used are not strong enough to tie all loose ends, the verdict will be given an (INCONCLUSIVE) as well, to signify that this will be re-checked in the future if more info is obtained. This also means that the current verdict might not be final and that you should take the verdict with a grain of salt, until more research has been done.

Reason: More information and explanation as to why this verdict has been given.

The List

Keep in mind that I only know what I know. While my investigations tries to eliminate as much subjectivity as possible, there are some cases where it is unrealistic to through all the possible cases just to draw a verdict. The amount of time I'm willing to research on a topic is not infinite, hence I try to draw a general consensus here by comparing the major points. In case I'm missing something in which you find it worthy to be added to the list or if you disagree with my conclusion, feel free to message me and I will hear you out/start an investigation.

Without further ado, enjoy!

Yellow guns are better on CL(T)

The claim

Investigation

The origin stems from when CL fit bonuses was introduced. Since the battleships are known to have overweight penalties, rumors quickly spread around that CL(T)s suffer overweight penalties from equipping 20.3cm

or anything of similar caliber.

While it is true that are now just as viable on CLTs, since CLTs lack the ability to artillery spot, it does not necessarily mean that are inferior. The same applies to CLs, it has not been proven that 20.3cm

counterpart have lower compared to the other guns, but is undefeated when it comes to giving stats. It is also one of the few guns that give fit bonuses on CL, CT and CLT, which further increases the bonuses and the to compensate the lower firepower stats of the guns. Note that the fit bonus only applies when at least 2 of them are equipped and the fit bonus gets very harsh diminishing returns for every fit gun you use.

Cannot double attack?

An interesting question was raised after this was published. "If a CLT is equipped with a Minisub

, doesn't it effectively prevent them from double attacking during the night if you give them ?"
The answer is, no, because one thing that differentates a Minisub

?

are shit, I've only said that they are not necessarily better than the other guns available on CL(T)s. With that said, if you have neither of them, it's perfectly fine to keep using yellow guns, as long as the reason is not "but I thought red guns were overweight".

Verdict

FALSE

Reason

This whole false meta started spreading because of some misconception where people thought overweight mechanics apply on ship classes other than (F)BB(V) as well. There's no scientific explanation as to why red guns should be inferior to yellow guns, so this is a case closed for me. People should just decide which guns to equip by stats alone, whether they are , or .

is the best carrier

The claim

Kaga is still the best carrier in the game, because of her 46 plane slot.

Investigation

Back when the Aircraft Proficiency didn't exist yet, obtaining the necessary fighter power to obtain AS/AS+ was a hard thing to do, which is when the meta to equip fighters on the largest slot sprung to live. Obviously as Kaga has one of the biggest plane slot, she was hailed as the best carrier in the game.

Now with the inclusion of Aircraft Proficiency, fighters gain flat fighter power boosts which increases with each rank, and because we now have a better understanding as to how Aerial Combat works, fighters on smaller slot sizes are preferred nowadays. Also with the inclusion of the CVB, Kaga

fell out of favor as the favorite, since being able to shell during 中破 matters a lot.

is definitely not a weak ship and she's still excellent, but she is by no means the best carrier in the game. If Kaga

does not perform better in all reasonable scenarios, then the claim that she is the best carrier is ridiculous. For someone who does not have the highest stats of her class and also lacks advantages which only CVB has, you can hardly call her the best, it simply doesn't work that way.

Isn't it unfair to compare a CV with a CVB?

In normal circumstances, yes. But the fact is, the branching rules takes no distinction between CV or CVB, unlike battleships where each category is treated differently. If the branching rules treat CV and CVB the same, then it means that there is no reason to separate them.

Also, while CVB can shell during 中破 while a CV can't, it does not mean that their role is any different than that of a CV. This isn't the same as comparing a FBB with a BBV, or comparing a CA with a CAV after all. CVBs do have the advantages of being able to equip certain equipment CV can't use like jets, but that also doesn't change their role of helping your fleet maintain air superiority while dealing damage against your opponent through shelling. That's why I've also concluded that standard CVs shouldn't be given special treatment in this comparison.

Isn't total plane slots still just as important?

It's really stupid to insist Kaga is still the best carrier in the game, just only because her plane slots are better, but for the sake of argument, you can expand this section and continue if you're interested.

For those who are still not convinced and still insists that her plane slot still makes a world difference and takes priority above all else.

still has the highest amount of plane slots, that's for sure. But now that there's Aircraft Proficiency, each double chevron fighter adds up to around ~25 fighter power, making it easier for you to reach the requirements for AS/AS+.

Here's a comparison of the planes with fighter power calculated with the estimated fighter power bonus from proficiency applied, and the opening airstrike damage calculated using the formulas here:

So while there still is some difference regarding plane slot sizes, it becomes less significant as admirals get stronger planes as they progress. While the comparison are similar, remember that the bigger the slots, the more plane loss they suffer because of proportional shotdowns. Even ignoring the argument of costs, considering that Shoukaku Kai Ni A

With that said for bombers, how about fighter power? Surely her ability to obtain the highest amount of fighter power would surely matter in some scenarios, right? For Kaga

to actually triumph over the others, the following case specific scenario has to happen:

The branching rules restricts the use of CV(L/B) to 1.

Establishing air superiority is only realistically achievable through only Kaga

, because of her plane slots, if we talk about carriers only in general. This means that Kaga

has to be able to defeat all contenders when it comes to the usefulness of plane slots.

There are no alternatives like aviation ships with seaplane fighters or that option is not available because of the lack of equipment/ships.

There actually is no map that I could think of that fits all these criteria, but by bending the rules a bit, the map that fits this the most is 6-1. The fighter power requirement for 126/252 for AS/AS+ respectively on the boss node, so let's see if she also dominates that map.

The fighter power requirement for getting AS+ is 252. It is a bit of a stretch to obtain 252 fighter power depending on the quality of your planes and I honestly personally don't recommend this idea if you're ever going to tackle 6-1, but it is an option nonetheless and for argument sake, it is investigated.
There are a few important criteria that I keep in mind:

Do you have to fighter mule the CV(B) or can you squeeze a bomber in a decent slot?

Does stronger fighters affect the result?

What is the damage potential?

Keep in mind that CVB have a lot more advantages and that they generally have higher base stats over a CV. In case Kaga

fails to make an impression with her plane slots, she loses by default.

gains the fighter power numbers 83/70/59/55, which adds up to 267 fighter power. It's the same scenario for Shoukaku that she cannot maintain AS+ if she were to replace one of the fighters with a bomber.

cannot obtain 252 fighter power with only 2 slots, it's impossible regardless of which fighter you use. Obtaining at least 252 fighter power with 3 slots is actually possible now, but in all cases, it is forced to utilize the 46 slot. Considering how it allows Kaga

to shell, it is but a small price to pay that you cannot utilize the 46 slot with a bomber. Plus point is that a bomber can be used on the first slot. Can Shoukaku Kai Ni A

can indeed do the same, but it comes with a flaw. In all cases where AS+ is obtained, you are forced to equip the bomber on either the 12 slot, or the 9 slot. Using a bomber on such a small slot is generally a bad idea, considering that your opening attack is weaker and you face the risk of it being wiped out by fixed shot downs from the enemy tsu classes

has one of the most balanced slots of all the carriers, which makes her a rather big contender. By using a Iwai, Iwamoto and a Reppuu (601) she gets up to 264 fighter power, which is more than enough for AS+. It also leaves a 18 slot size for a bomber to utilize. The difference between 18 and 20 torpedo bomber is really negligible and as the base stats of Saratoga

is the best carrier. From the above example, we also see that balanced slots is way more important than just simply having a giant plane slot.

Besides that, there are also a few problems:

Aiming for AS+ instead of accepting AS is a bad strategy to begin with, if you're forced to restrict yourself on bombers that much and are also forced to displace bombers in a weaker slot. Not a healthy idea when the whole map is roaming with plenty of enemy tsu-classes

has a 20 slot bomber equipped and a first slot to boot, her situation is not that far off from Shoukaku

. While Shoukaku is obviously at a higher risk of her bombers being wiped out, a 18 slot or a 20 slot bomber are at risk as well.

I hadn't even added the factor of using your SSV on that map as seaplane fighter mules. Alternatives do exist, and when they get added to your fleet, it basically changes as to how demanding fighters are on carriers.

Scenario 1

has 69/69/92/59 fighter power values depending on the slot, you can actually reach the goal of at least 126 by using the 2nd and 4th slot with a Reppuu

, while reserving the rest of the slots with bombers. You will barely reach the goal with 128 fighter power, but don't forget that double chevron bombers also helps contribute to the fighter power, which helps push the fighter power to around 130~136. This leaves her 20 first slot and her giant 46 slot available to be utilized by bombers. Thats 124 and 154 damage respectively, assuming a 1.5x roll from a Ryuusei Kai

has 83/70/59/55 fighter power values distributed over her plane slots. It's actually noticeable that Shoukaku has a bit more trouble getting the required fighter power while utilizing as less slots as possible, as she does not have bigger plane slots, in comparison to Kaga

is also stretching it a bit thin with only 126~132, because there is a high risk that your fighter power might drop below the requirement at the time you reach the boss. The chances are decent though if you use Tomonaga and Muratas instead, with a fighter power of 134~140, but the risk of it being wiped by enemy tsu classes

has 79/73/73/53 fighter power values from her plane slot distribution. A rather unexpected contender, as her 3rd and 4th plane slots adds up to exactly 126 fighter power, which can be further pushed by double chevron bombers. A 30 first slot and a 24 slot aren't exactly small either, which is equal to 144 and 133 damage on a 1.5x roll of a Ryuusei Kai

has a better optimized damage output in the same situation, something in which Kaga

's giant 46 slot fails to compensate.

Scenario 2

With all restrictions lifted, all carriers listed are capable of hitting the necessary fighter power by only utilizing 2 of their smallest slots. Since air power is basically pointless to delve into further, it basically becomes a comparison as to which carrier deals the best damage potential. Since I've already established before that Kaga

will not surpass others in term of damage potential, this scenario is basically a repeat of what I have mentioned above.
I'll show the comparison here again, I assume everyone uses Ryuusei Kais

Verdict

Reason

is by no means useless, she is definitely no longer the best carrier in the game for too many reasons provided in the investigation. Once again, if Kaga

does not perform better in all reasonable scenarios, then the claim that she is the best carrier does not hold. As stronger planes become available, having a giant slot is no longer as significant as it is back then and when the CVB and Aircraft Proficiency appeared, this meta was broken.

Also, considering situations where you are only allowed up to using 1 CV(B) is incredibly rare, and even if such a situation occurs where one of the cranes fails to reach the necessary fighter power, there are alternatives like Taihou

equipment works like any other cut-in booster

The claim

will help boost the cut-in chances of the ship the same way the other equipment does.

Investigation

How much luck affects the cut-in chances is still a mystery to this day. While the exact values are still unknown, we know for sure that 50 is the softcap, as past that number, luck barely increases the chances of cut-ins. What is also discovered, is that Skilled Lookouts

doesn't do anything if it is equipped on a ship who already has 50 or more . This makes the Skilled Lookout severely underwhelming, since all the other equipment are post-cap bonuses and buffs the whole fleet.

Verdict

QUESTIONABLE(INCONCLUSIVE)

Reason

is vastly inferior when it comes to buffs and it does not help improve ships who already have 50 . In the rare circumstances that you actually have a free slot available and you really have nothing else worth equipping, you could consider using the Skilled Lookout. But even without knowing the exact value the Skilled Lookout provides, it's obvious at the moment that there are plenty of better alternative uses for the free slot.

Always put TCI ship on last slot

The claim

You should always put the ship who is performing the torpedo cut-in on the last slot of the fleet.

Investigation

This is actually a known recommendation by most veterans. The theory basically is that the weaker ships could either help clean up the escorts or help deal scratch damage against a high HP target. Since scratch damage deals proportional damage to a target's current HP, having a weak ship do scratch damage is usually advantageous.

After the escorts are cleaned up or if the boss is weakened enough, the ships loaded with torpedo cut-in setups are there to finish off the boss. In case there are still escorts alive, this setup still gives the last ship the best amount of chances to hit the boss.

While there is generally no problem with this, this strategy however, assumes that your TCI ship is indeed the strongest attacker. When you are using weaker ships like Hatsushimo

Verdict

OK

Reason

The real reason as to why people recommend you to put TCI ships on the last slot, is because the ship with TCI is usually your strongest attacker. The reason is not because the ship is using TCI, its because the ship deals the most potential damage. With that said, even though I gave this an OK verdict, you still shouldn't mindlessly put all TCI ships to the end without first checking out what the damage potential is of your fleet. You should also definitely consider the possibility of flagshipping your TCI ship instead, which grants a bonus to your cut-in chances.

Abyssal ships can AACI

The claim

Abyssal ships can perform AACI.

Investigation

This rumor actually became rather popular, after bombers sent against Kitanda

mysteriously all drop like flies, as if they all had been shot down from an AACI.

What people didn't realize though, is that those 2 enemy classes have one thing in common, they both are equipped with Twin HA guns, instead of the single ones that the majority of the enemy carries. Since an abyssal Twin HA gun has a high AA modifier compared to an abyssal Single HA gun, which has a zero modifier value, the AA attacks of those classes will obviously become much stronger as well. Using this knowledge and the Abyssal AA formula, you will easily come to the conclusion that the shot down ratio is not caused by AACI fire.

?

s are just as big of an offender as the above 2 examples. They are equipped with Coastal Radar, which functions as an Air Radar and their forms come with both Twin HA guns and AA Machine Guns. As have a modifier of 6, instead of the 4 from , they are way more dangerous to your planes, yikes.

Verdict

FALSE

Reason

There has been no known scenario of abyssal performing AACI so far. Considering how difficult it is to understand the aerial defense formulas, it comes to no surprise that people would claim that abyssal could AACI.

Echelon is the best formation for night battle

The claim

When being sent to a night battle, choose Echelon for the highest chance for survival.

Investigation

People recommending Echelon during night battle are those who mainly aims to increase your evasion as much as possible, instead of actively killing everything with high accurate shots. As this is the complete opposite of Line Ahead, where you actually actively kill everyone before they kill you, it would be a moot point to approach it this way and compare those 2. Instead, we compare it with 2 other similar defensive formations: Diamond and Line Abreast.
For this scenario, I have prepared 2 sources: test samples of 5-3 and data mined from KC Kai.

A quick glance on the data from KC Kai tells us that the Echelon obviously does have higher evasion than Line Ahead, but still lower than Line Abreast. Diamond is seemingly the most unimpressive one, so that's obviously ruled out. Both Echelon and Line Abreast suffer from the same amount of damage and accuracy penalty, save for Line Abreast having an even worse torpedo accuracy, which only applies during day and is thus irrelevant. Line Abreast basically has higher evasion, for nearly the same handicap. Since this is actually KC Kai data, it might not apply to the browser version, hence we continue with the next sample.

The 2nd sample shows bizarre results on the evasion chart, because of the small amount of samples. Notably though, Line Abreast and Echelon are both dominating again in the majority of comparisons when it comes to evasion, and a lot of cases, Line Abreast is better than Echelon. Even with low sample size, its a sign that the evasion of Line Abreast is close or maybe even better than Echelon.
The accuracy tests however, comes with a larger sample and in majority of the cases, its marginally better than Echelon. This seems to differ from the data from KC Kai.

Verdict

FALSE(INCONCLUSIVE)

Reason

Because of the lack of samples, we cannot tie up all loose ends, but considering that there are plenty of evidence hinting that Line Abreast is superior to Echelon, I would have to conclude for now that Echelon can't be the best formation to pick for night battles.

The claim

As using torpedo equipment on CLT benefits their daytime opening torpedo as well, they should always be using torpedo cut-in setups. After all, Kitakami

has above average base luck and TCI deals huge amount of damages.

Investigation

The people claiming this aren't exactly wrong actually, but they miss a few too many details, which makes this a flawed option. To tackle this, you first need to know how damage calculation works.

During day, all your attacks are softcapped to 150, while shelling is capped to 180. In case your damage output goes over it, the remainder past the cap will get square rooted. There's generally no reason to go over the day cap, especially if its torpedo stats, since everything past it will come with heavily diminished returns.

One of the reasons people recommend using TCI on them, is because they claim that the torpedo equipment apparently also benefits the opening torpedo. Well, let's check it out.

torpedoes only raised the damage by 4, it's obviously a blatant ripoff if you could optimize your setup in a better way. Instead, using 2x 20.3cm(3)

raises your shelling power by 20 just fine, so that the torpedoes benefit your day shelling is obviously nonsense, if the guns do a better job in it. One might argue though that this helps improve your damage in case you roll a head-on or Red-T engagement, but consider either only happens 40% of the cases while it is pretty much useless on Parallel and Green-T, that is not a good reason to justify your use of TCI. There's also the reason that there is still room for improvements on shelling , which improves the ship in all engagement modifiers.

Night Battle

Night battle damage is basically + combined, which is further amplified by special attacks. Unlike artillery spotting, night special attack is not post-cap, so it will be nerfed by the 300 damage cap during night. The DA gives you 2 attacks with a multiplier of 1.2x, while a TCI gives you 2 attacks with a multiplier of 1.5x. While the TCI looks like it is one strong attack, it is in actual 2 separate attacks that is combined into one.

Multiply it with the TCI multiplier of 1.5 x 238 = 357.
Since the total goes over the 300, the remainder gets square rooted, the final number being 307.5.

Luck factor

Now you must think be thinking: "There's a clear difference of 27 damage, obviously the TCI is better, right? and you wouldn't be wrong if that's the only thing. The difference between DA and TCI is that DA has a 99% chance to trigger, while TCI is completely luck based.

are already capable of dishing out high amount of damages through DA, and allowing them to TCI only increases their damage up by 27, while if you luckmod Yuudachi

instead, the difference in power between her DA and TCI is nearly 100 damage! That's damn a lot.

Alternative scenario: Improved Equipments

While the analysis above shows perfectly how it could be a bad idea if you attempt to use TCI without the knowledge of what you're doing yourself, there is still room for discussion regarding improvements.
This is what we know about their damage potential:

looks less and less feasible, especially if it only takes a few screws of investments to narrow the damage potential.

Cases where TCI actually is mandatory

So are there any cases in which TCI is actually necessary for you to be able to effectively deal damage to a boss? There actually is one case and that is against Kitanda

, who has a ridiculous value of 333 . Even with the debuff, the armor value would still be ridiculously high to the point where you have to pray that you get both a lucky armor roll and a critical hit in.

and are forced to use a TCI setup. But considering this, it might change in the future event maps.

Alternative scenario: Moderately damaged state

Ships in 中破 state suffers a 30% firepower penalty, but in turn, gains an increase in CI chances. Being in 中破 is obviously kind of bad, but can the risk of being in 中破 justify the use of TCI? Lets find out.
This is the damage potential in a healthy state:

Day Shelling

For using torpedoes instead of regular main guns, you get the situation where you would do 17 damage more, but at the cost of dealing 14 damage less. Using a TCI thus doesn't really justify the day phase, considering how marginal the difference is. If anything, we would have to look at the night battle to see if there's a noticeable difference.

Night Battle

The average armor of a boss is generally around 170 while on harder difficulties, it's estimated around 200 . With the damage penalty in effect, a Kitakami

with DA setup will obviously fail to do any reasonable amount of damage, while a TCI still can dish out a reasonable amount of damage.

However, while the TCI chance has increased because of the 中破 state, 52% isn't a surefire number that would always trigger either. If you want it to be a bit more reliable, you would still have to invest Maruyus

into them for the marginal chance that your ship does end up in 中破.

A 50+ increase in night firepower isn't exactly low either, which TCI does compensate somewhat. However, you're honestly not waiting for your ships to get hit and flip 中破 state, since it also impacts all other phases. This is arguably cost inefficient if you were planning to invest Maruyus

on them, just to make them more useful if they took a hit. Also consider the times where your CLT actually does end up in 中破 state and not flat out 大破 or 小破.

Don't get me wrong, being able to do 50+ more damage in 中破 is definitely an advantage, but it demands some investment and there are probably a lot more measures you can take that actually decreases the chances that they actually would end up in 中破 instead. You also have to pay the price of having a lower in favor of , so it's not surprising if you suddenly cannot take down some of the weaker enemies during the day shelling.

TL;DR

would improve your day torpedo attacks, it does not necessarily mean it's better if the improvement barely adds values to your already existing damage potential. Its a rather bad idea, considering that you basically already hit day cap with only a minisub

, its simply no excuse to recommend TCI over DA. A healthy DA attack deals 280 damage, and this gap to the night cap gets closer as you keep improving those guns.

On the other hand, it does improve your situation a bit if either somehow ends up in a 中破 state, but it's a rather situation specific and you much rather want to avoid being in that zone. Not to mention that you're investing into preventive measures instead of allowing some of the weaker ships to effectively hit night cap through TCI, this means it doesn't add much value if the ship doesn't actually end up in 中破 state.

Verdict

Reason

anyway. I've only given you the best optimization advice, who am I to stop you from letting you play however you want? While that doesn't mean I'm telling you not to ever luckmod them, you should consider your priorities and luckmod those who benefits the most from being able to TCI. Luckmodding a ship takes a lot of investment, choose carefully on who to spend your Maruyus

on the main fleet in Combined Fleets

The claim

Investigation

This rumor sprung up when some of the newer faces first got to taste the horrors of having to fight against an Installation boss. When they first learned of their weaknesses, one of them being the Type 3 Shell

have an armor value of around 90 , they do not share the same weaknesses as soft installations.

There exist a day damage softcap of 150. Since the main fleet do not participate in night battle, they cannot unleash the full potential by getting a 300 night battle softcap.

In other words, even if the main fleet is equipped with the respective weaknesses, they still wouldn't be able to do much helpful things against installations in the majority of the cases during day. You might as well optimize your fleet in a better way by equipping AP shells instead to enable post-cap bonuses.

In case of CA(V)s in the main fleet, you might be able to get away with using a Type 3 Shell

on the easier difficulties, but the escort fleet benefits way more when the damage softcap is increased during the night. This isn't realistic when on harder difficulties, the enemy armor way exceeds over the day cap in which case, you would do scratch damage regardless of whether you have a Type 3 Shell

equipped or not. In this case, I would suggest using a instead to maximize your DA chances.

Verdict

FALSE(INCONCLUSIVE as day shelling is now 180)

Reason

Really, don't waste your time by equipping anti-installation equipment on the main fleet in general, as you wont be able to efficiently punch through their base armor anyway during day. Just focus on equipping AP shells instead for your (F)BB(V) to deal with all the other threats, as they carry a postcap bonus which in the end will help you a lot more than a Type 3 Shell

does, while letting all the escort fleets do the anti-installation work during night battles.

Flagship can always perform AA, even without stats

The claim

The flagship of a fleet can always perform AA attacks and shoot down planes, even if they have 0 stats.

Investigation

The origins of this myth actually came from multiple locations, but the most recurring ones are people complaining how the enemy subs could still shoot down their planes on a CVL in 1-5 and how a full sub fleet could shoot down enemy planes. After all, since the subs have 0 stats, its impossible to explain how the planes gets shot down, unless the flagship by chance always performs AA attacks, right?

This is basically another case of people failing to understand the Aerial Combat mechanics, which caused the rumor to appear among the community. To understand the process, you need to understand how the planes gets shot down in each phase. For that, we will only look at the 1st phase of Aerial Combat, since its the most relevant to our topic.

1st Phase

All Fighters/Bombers participate in this phase to establish the air control, which can either be AI/AD/AP/AS/AS+. Since you would either have a sub fleet, or you would be fighting against subs, we will assume AS+ in all scenarios for the party with aircraft. Also, during the 1st phase, all planes are immune to fire. One might wonder then how in the world the plane gets shot down during the 1st phase.

Well, if you check out this table, you will notice that even in the best possible air control, you face a proportional shot down of 7/256～15/256 that is actually caused by the air control itself. That's right, whether there is an opposing fleet or not is irrelevant, your plane will magically get shot down out of nowhere by a game mechanic that decides the air status.

This basically means that even if you face an opposing fleet who has no stats, any plane slot count that is 18 or higher is still at risk of being shot down. Of course on AS+, the loss is at most 1 or 2 planes, but it gets progressively worse on worse air states. This is also another reason why you're recommended to achieve the highest possible air state you can manage, to lessen the amount of planes lost from a proportional shot down out of nowhere.

Of course there is. Since submarines have no stats, it means that none of your planes are at risk of being wiped out from a fixed shot down fire during the 2nd phase. You also have to understand that a plane slot size is not a relevant factor as to how much damage you deal against a submarine. Only stats apply, and that is not scaled by a plane slot size.

1 or 2 plane loss is really small though, but if you insist on wanting to save , avoid using bombers on plane slots of 18 or higher in the future and instead, use either a plane that cannot be shot down like the Saiun

or replace it with a non-plane equipment.

Verdict

FALSE

Reason

Well, I've mentioned it before and I honestly don't blame anyone for not understanding how the Aerial Combat works, but you can see how easy it is for false rumors to appear when this is not fully understood by people. The explanation is only one part of it, since I haven't covered the 2nd phase as well, but the explanation above should be enough to confirm that this rumor is false.

AP shells effect applies even when in a support expedition

The claim

grants a damage bonus, even if the AP Shell is equipped on a ship in the support expedition.

Investigation

This rumor started to appear around the time when the received a buff, which allows it to grant a post-cap damage multiplier bonus against certain enemies, when equipped on battleships. Of course as this works during sorties, people were also speculating that it might also work on support expeditions.

The tests actually has been carried out long ago to verify whether this even works or not, this one being an example not long ago, and this one even dates back to 2015.
Regarding support expeditions, the following is known:

Literally almost everything that does work in regular sorties will not work when used in support expeditions, which includes AP shell modifiers.

Verdict

FALSE

Reason

AP shell modifiers do not work in support expeditions at all, except of the base stats it gives. It's almost as if people accepted this rumor as truth, even though it was never confirmed at all whether it works or not. The myth was already busted around 2015 or probably even earlier, and it is rather ironic that some people are still advising others to use AP shells on support expeditions to this day anyway.